Last year, two men claiming to be members of the Cherokee Nation who had traveled from Oklahoma came to Seattle with a simple goal: score some scrap copper.

Dressed in beads and fringed suede, with one wearing a cap that said “Native,” they headed to the offices of Seattle City Light, where they chanced upon its superintendent, Jorge Carrasco, in the lobby. They told him they ran a nonprofit that taught disabled children how to make jewelry and needed some copper wire.

Minutes after meeting them, Carrasco authorized the men to be given some scrap.

But the two were actually con men. Once inside City Light’s secure facilities, they were able to drive off with 20 tons of copper wire and scrap metal worth $120,000.

Police described the two key suspects, Michael George (aka Michael Little Bear) and Jim Costa (aka Joe Wolf), as organized criminals who have pulled off scrap-metal heists across the country. Seattle police later recovered the stolen copper.

A detailed account of this episode can be found in records recently compiled by The Seattle Times, including police records, a 2013 internal report by City Light and an audit by the city of Seattle released June 6.

City Light’s news release about the theft, thanking police for recovering the copper, did not disclose Carrasco’s role.

Because of his involvement, lower-level supervisors and employees who helped the suspects load the copper into a rental truck, but suspected something was wrong, said they didn’t speak out because they were afraid of being considered “insubordinate or disrespectful.”

Carrasco, the city’s highest-paid employee, whose pay range was recently raised to as much as $364,000, was unavailable for an interview.

It all started around 8 a.m. on April 23, 2013, as Carrasco waited for his coffee at the Seattle Municipal Tower Starbucks. He was introduced to the two men by a City Light manager who had met the two minutes earlier. They gave their names as Michael Little Bear and Joe Wolf.

The men told Carrasco that his predecessor, Gary Zarker, had previously donated copper to their nonprofit. They said it taught disabled children the native language and showed them how to turn the scrap into trinkets and jewelry they could sell to raise money.

Carrasco asked for a business card so he could contact them later, but the suspects explained they needed an answer right away because they were leaving Seattle soon and had a bus with “35 kids” that was circling the block because it was too hard and expensive to park nearby.

If they wanted help today, Carrasco said, they would need to wait until he found someone available. While waiting for his drink, Carrasco called his assistant and told her to have Bernie Ziemianek, a director of operations, come to the superintendent’s office immediately.

After the two suspects arrived with Carrasco at his office, they gave what they said were examples of their work — belt buckles, bracelets, necklaces, dream catchers — to Carrasco, his assistant and other City Light staffers.

Carrasco dispatched Ziemianek to oversee the donation of “a small amount of scrap material” at the Seattle City Light South Service Center on the 3600 block of Fourth Avenue South.

The facility houses one of the utility’s larger substations and serves as storage for transformers, poles, wires and scrap metal left over from system upgrades. The utility routinely sells the metal to recyclers.

To carry out Carrasco’s orders, Ziemianek called warehouse manager Brent Schmidt, construction manager Richard Moralez and material-handling supervisor Nancy Daily to meet him and the two visitors at the salvage yard with two hard hats.

When the suspects arrived, a security officer wrote down their names and the license-plate number of their rented silver passenger van but failed to inspect official IDs.

The group was soon joined by Rosauro Cayetano, a salvage-crew chief, who showed them around the yard to different piles of scrap metal.

Ziemianek later said he had authorized the suspects to take “a few” pieces of copper from the three locations, but other employees said they did not hear such directions. One supervisor at the yard later told an investigator he believed that the suspects had a “blank check.”

As Ziemianek was leaving the facility, he told the security guard that the men would be returning with a small truck to load the copper and he should call Daily with any questions.

Daily left shortly after Ziemianek and placed responsibility on Cayetano, who typically handles the loading of salvage materials without supervision.

When the suspects returned with a Penske truck, Cayetano supervised the weighing of the truck on the way in. Then he and another employee “personally assisted the suspects with loading the truck,” the report said.

All along, the suspects engaged the employees in constant conversation, discussing everything from Native American medicinal plants to upcoming powwows. After the suspects drove off in the yellow Penske truck, they returned with a second, identical truck. The security guard thought it was the first truck, returning because the suspects had forgotten some paperwork, according to the city’s internal report.

As three City Light workers helped Costa and George load the second truck, Cayetano “got the feeling that they were taking too much copper.” He attempted to call Ziemianek, as well as other supervisors, but reached no one. He didn’t leave a message.

In a panic, Cayetano called Steve McClintock, another warehouse crew chief at the South Service Center, and told him to look out his window because “something was not right.” McClintock came over and told the men to stop loading the Penske truck.

One of the suspects replied that they had received copper from two former City Light superintendents, dropped their names, and reassured McClintock that with this much copper “they would not need to come back for eight years again,” according to the report.

Suddenly one of the suspects said they learned a child in their group had had an accident and they needed to leave immediately. As with the first truck, Cayetano made them weigh this truck before they drove off. It was 12:34 p.m. and the suspects had heisted 40,450 pounds of copper.

The Seattle Police Department later learned the copper wire was shipped to Fort Worth, Texas, to American Recycling, where the men were to be paid $100,000.

Seattle police records also show that George and Costa, using the ruse of running a charity for disabled Cherokee children, completed a similar scheme that April at SAFE Boats in Tacoma and Bremerton. The company builds specialized boats for military, law-enforcement and fire departments.

They sold the metal they scored at SAFE Boats for $8,600, a police report shows. A SAFE Boats employee told police no one asked for photo ID or a tax number identifying a charity.

Police described the men as members of a family of Romanian “gypsies” carrying on a “nationwide scam” that included “father, son, grandkids and son-in-law.” Police said the men were involved in metal thefts totaling several hundred thousand dollars in Crystal Springs, Miss.; Lewiston, Maine; and San Antonio, Texas.

In December, King County prosecutors charged three men — Michael George, Jim Costa and a son, Nick Costa — with first-degree theft and first-degree trafficking in stolen property. The men made bond and have missed court appearances. Their whereabouts are unknown.

At City Light, Chief of Staff Sephir Hamilton said no one was disciplined. Two of the employees involved either didn’t return calls or chose not to comment.

“Ultimately we found a problematic pattern of being able to exploit the policies and procedures we had,” Hamilton said. “We took it as a learning opportunity and took it to heart what happened, which was these scammers exploiting human nature.”

He said the agency “developed this comprehensive internal campaign to make sure that people weren’t going to be scammed again.”

After the theft, City Light set rules about charitable giving, he said. They require that all requests be put in writing, receive approval by the chief of staff, and be of benefit to City Light and its customers.

“The big thing is stressing that there are no exceptions,” Hamilton said.

Also, he said, City Light has added more security cameras to its facilities.